According to
http://support.apple.com/kb/HT3634
You can’t get your birthday calendar onto the ipod touch or iPhone, but here’s a workaround as per:
iPhone 3.1: Explaining Subscribed Calendars and Mobile Me | MyAppleGuide
I pulled this off successfully. Here is the summary from the page mentioned above:
Syncing Birthday Calendars with iPhone, Mobile Me & iCal
Concerning Birthday calendars, please note:
While a Birthday calendar may appear in the Subscriptions calendar of iCal, it is not a normal subscription calendar, and cannot be added to your iPhone/iPod touch.
This is the workaround I use:
- Publish the Birthdays calendar in iCal to Mobile Me (right click and choose publish) and select ‘publish changes automatically’.
- Email the calendar to yourself.
- Open the email on your iPhone and subscribe to the calendar.
- In Mobile Me, navigate to your calendar preferences and select ‘Show birthdays calendar’.
Now if you add a new contact on your Mac or iPhone with a birthday, it will automatically be added to your birthday calendars .
Extra Notes
Currently in iCal, there is no way of specifying which calendars you would like to sync, and as such, all your subscribed calendars will sync with your iPhone/iPod touch. Unfortunately, the only way to prevent this is to remove the calendar from iCal.
For more information, check out these support documents from Apple:
http://support.apple.com/kb/HT3634
http://support.apple.com/kb/TS1213